Welcome to TTF.
Yeah, that's a problem with Favourites, namely, renaming them and, as a consequence, losing the address.
Here is a somewhat convoluted method that should work:
The favourites are saved in the mapsettings.cfg file stored in your specific map folder.
Download POI Edit from here:
PoiEdit - Main
Open the mapsettings.cfg file within POI Edit.
Every item stored in the .cfg file will appear in a list in the right pane along with the lat/long. In the left pane, a map will show with its location.
When you see your favourite on the map, if your model has the facility, then navigate to-->lat/long, and put in the values from POI Edit's screen. See where it takes you.
Told you it was convoluted.
Hopefully, someone will come along with an easier method.